Wireless communication systems are widely deployed to provide various types of communication content such as voice, data, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., bandwidth and transmit power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems.
Generally, a wireless multiple-access communication system can simultaneously support communication for multiple wireless terminals. Each terminal communicates with one or more base stations via transmissions on the forward and reverse links. The forward link (or downlink) refers to the communication link from the base stations to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the base stations. This communication link may be established via a single-in-single-out, multiple-in-signal-out or a multiple-in-multiple-out (MIMO) system.
In a communication system, the network consists of several base stations, each one of which communicates with one or more access terminals. Typical paging messages from the network are sent from a set of base stations (paging area) where the network determines that the mobile terminal is likely to be present. The area where pages are sent is called a paging area. The network resources required for paging increase with increase in the paging area. Thus, it is a desirable to minimize the paging area. The paging area is typically decided based on registrations, where the mobile terminal communicates its current position to the network.
In a wireless communication system, registration is the process by which the mobile terminal (i.e. access terminal) notifies the network of its location, status, ID, and other characteristics. The registration process allows the network to know how to find the access terminal so that it can page the access terminal when there is an incoming voice or data call. In order to conserve power (i.e. battery life) the access terminal enters into a power save mode. Another method is to reduce the number of times an access terminal registers with the network. The act of registration requires the access terminal to exit the power save mode and set up recourses to communicate with the base station.
Traditional methods attempt to conserve power by reducing frequency of registration. This may work well for those access terminals that are not mobile or stationary. However, reducing registration equates to the network increasing its resource to page the access terminal to ensure that the access terminal will receive a page, since the access terminal may be mobile (for example, traveling from one base station to another) within the network.
Thus there is a need to have method of adaptively adjusting the registration area and the paging area for access terminals that are mobile.